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SAE J2735-Draft-Rev15 [issued: 01-30-07]
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This is an SAE Motor Vehicle Council draft document of the DSRC committee, subject to change.
7. DATA ELEMENTS
Messages and data frames specified in Clauses 5 and 6 shall be composed of message elements. Any message
or data frame specified in Clauses 6 or 7 shall have all of its DEs specified in this clause, except those DEs that
are primitive ASN.1 data types or those that are adopted from other functional areas, or defined in other volumes of
the family of standards. In the later cases, the referenced standards shall be consulted.
Regarding equivalent entries to be placed into a data registry. The mapping between data elements and analogous
meta data entries have been explained in other ITS stds. In addition, some meta information is constant in this
entire standard and need not be repeated with each entry here. These include the sponsor and steward of the
entries [SAE], the registration status [registered once the standard is adopted] and the revision date [the date of
the standards adoption]. The class name is always ITS.
The productions of ASN.1 which follow shall be considered normative in nature. While the majority of the normative
content is reflected in the actual syntax of the ASN.1 some entries also have additional statements in the ASN.1
comments which shall be considered to be normative as well. In addition, the commentary provided with each
entry may also provide additional normative restrictions on the proper use of the entry which shall be followed. The
XML productions follow directly from the ASN.1 specifications and the same rules shall be applied.
7.1 Data Element: DE_Acceleration
Use: A data element representing the signed acceleration of the vehicle along some known axis in units of 0.01
meters per second squared. A range of over 2Gs is supported. Accelerations in the directions of forward and to
the right are taken as positive. A 2 byte long value when sent.
Longitudinal acceleration is the acceleration along the X axis or the vehicle's direction of travel in parallel with a
front to rear centerline. Negative values indicate braking action.
Lateral acceleration is the acceleration along the Y axis or perpendicular to the vehicle's direction of travel in
parallel with a left-to right centerline. Negative values indicate left turning action and positive values indicate right-
turning action.
ASN.1 Representation:
Acceleration ::= INTEGER (-2000..2000) -- LSB units are 0.01 m/s^2
XML Representation:
<xs:simpleType name="Acceleration" >
<xs:annotation>
<xs:documentation>
LSB units are 0.01 m/s^2
</xs:documentation>
</xs:annotation>
<xs:restriction base="xs:short">
<xs:minInclusive value="-2000"/>
<xs:maxInclusive value="2000"/>
</xs:restriction>
</xs:simpleType>
Used by: This entry is directly used by the following 3 other data structures in this standard (record type, descriptive name,
ASN.1, and XML name (if present) of each):
DF
DF
DF
In addition, this item may be used by data structures in other ITS standards.